Vehicular door panels are formed to define a flange that extends around a periphery of a window opening. A plurality of retention clips are attached to an outer belt weatherstrip, and attach the outer belt weatherstrip to the door panel. Accordingly, the retention clips secure the outer belt weather strip relative to the door panel. The retention clips engage both the flange of the door panel and the outer belt weatherstrip in a snap fit interlocking engagement. The retention clips should be designed to prevent the outer belt weatherstrip from rocking back and forth on the flange or presenting a spongy or loose feeling.